Adapter for a multi-channel, low input capacitance signal probe

An adapter for coupling a multi-channel, low input capacitance signal probe head having input signal contact pads to a connector having one of a closely mating plug and receptacle mounted on a circuit board of a device under test with the plug and receptacle having high speed, controlled impedance transmission lines disposed within respective housings with one end of the transmission lines forming contact pads at one end of the housings and the other end of the transmission lines forming electrical contacts at the other end of the housings with the electrical contacts engaging each other on mating of the plug and receptacle, the adapter comprising:

• the other of the closely mating plug and receptacle;
• a housing having opposing end walls and sidewalls forming a cavity that receives the other of the closely mating plug and receptacle such that the contact pads of the transmission lines are exposed at one end of the housing and the electrical contacts of the transmission lines are exposed at the other end of the housing, the housing having probe head retention members formed in the sidewalls and alignment flanges disposed adjacent to the probe head retention members and extending upward from the sidewalls;
• a substrate having top and bottom surfaces with the top surface having a first array of contact pads corresponding to the input signal contacts of the multi-channel, low input capacitance signal probe head and the bottom surface having a second array of contact pads disposed thereon in a pattern corresponding to the contacts pads of the transmission lines of the other of the closely mating plug and receptacle with the contact pads on the top surface being electrically coupled to corresponding contact pads on the bottom surface and the substrate having apertures formed therethrough that closely receive the alignment flanges on the housing with the contact pads of the transmission lines being affixed to the second array of contact pads;
• and
• the alignment flanges mating with corresponding bores in the multi-channel, low input capacitance signal probe head such that the signal contact pads of the multi-channel, low input capacitance signal probe head connect to corresponding contact pads on the top surface of the substrate with and the probe head retention members receiving attachment members disposed in the bores of the multi-channel, low input capacitance signal probe head to secure the probe head to the housing.